package priv.pront.code.robot.roboCom_uni;

import java.util.Scanner;

/**
 * @Description:
 * @Author: pront
 * @Time:2023-07-06 14:23
 */
public class P1914_小书童凯撒密码 {
    static int n;
    static char[] s;
    static StringBuilder sb = new StringBuilder();
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);
        n = scanner.nextInt();
        s = new char[55];
        s = scanner.next().toCharArray();
        for(int i = 0; i < s.length; i++){
            int cur = (int) s[i];
            if(cur + n <= 122){
                sb.append((char)(cur + n));
            }else{
                int mod = cur + n - 122 + 97 - 1;
                sb.append((char) mod);
            }
        }
        System.out.println(sb.toString());
    }
}
